The environmental credentials of battery electric vehicles were questioned at the latest Future of Technology seminar organised by the Advanced Propulsion Centre (APC) and Innovate UK.

Following a series of discussions by industry and environmental specialists, the event chair summarised by warning that electric vehicles will only deliver the environmental benefits that are expected of them if industry and government plan their introduction based on a much wider understanding of their true whole-life impact. Without this understanding, local air quality improvements could be at the expense of environmental damage elsewhere.

At the end of the seminar, delegates were asked ‘Is it right to push for more battery electric vehicles now despite concerns over the environmental impact of batteries?’ Only 55% of the attending industry experts answered ‘yes.’

APC states that the results from the audience and insight from seminar speakers provide yet more validation that organisations such as the APC must continue to be technology agnostic and support the research and development of a range of low carbon propulsion technologies, if the reality of a low carbon transport future is to be recognised.

The need to ‘see off’ internal combustion engines

The seminar began with environmentalist Jonathon Porritt CBE establishing the extraordinary threat that accelerating climate change now poses.

“This makes the transition from the internal combustion engine to alternative transportation technologies (hybrid, all-electric or hydrogen) all the more pressing, and that in turn demands significant breakthroughs in battery and storage technologies," he said. "Will super capacitors play a big role in that process? These are global challenges, but they will be resolved at the local level, on a city by city basis.”

Andy Eastlake, Managing Director of the Low Carbon Vehicle Partnership, set-up by the UK government to accelerate the transition to low carbon vehicles, followed by warning that a focus on tailpipe emissions alone, will blind us to other areas of environmental impact.

“50% of the current lifetime CO2 impact of an electric vehicle can be created during its manufacture,” he told delegates.

A major challenge, he believes, is identifying and developing the factors that governments use to influence the types of vehicles on our roads.

“Reducing taxation to incentivise vehicles with low tailpipe emissions is necessary to stimulate the market but does not yet enable us to influence the whole life emissions choices," he said. "Also, currently fuel duty tax revenues can help fund research into sustainable technologies, so new methods of taxing mobility will be needed.”

“To be effective, cleverly managed regulation and taxation should be simple in its objectives but sophisticated in its understanding of the issues," he continued. "Only then is it able to protect and finance, our long-term future.”

Beyond the tailpipe

Providing the delegates with an insight into some of the often overlooked aspects of electric vehicle manufacture and end-of-life recycling, Dr Allan Walton of Birmingham University’s Centre for Strategic Elements and Critical Materials pointed out that although rare earth magnets are high on the European Commission’s list of critical materials, less than 1% are currently recycled.

“Demand for rare earth magnets will rise rapidly with the growth in electric vehicles, yet these critical materials, the mining of which often has its own significant environmental impact, are extremely difficult to separate from other motor components,” Walton explained. “Designers of electric motors in particular must pay more attention to enabling cost-effective end-of-life recovery.”

Aluminium was provided as an example, with Innoval Technology’s Chief Scientific Officer, Professor Geoff Scamans, telling the delegates that the lightweight metal can only be considered a ‘green’ material in its recycled form.

“Making primary aluminium on average generates 16 tonnes of CO2 for every tonne of aluminium produced,” he stated. “Recycled aluminium from end-of-life scrap generates less than 0.5 tonnes of CO2 for every tonne produced so is considerably greener.”

ELG Carbon Fibre’s Technical Manager, Mathilde Poulet, said this is similar to carbon fibre reinforced composites, for which recycling uses only one tenth of the energy required for production from virgin materials. Additionally, the recycled carbon fibres are on average, around 40% less expensive than virgin carbon fibres and available on a range of short fibre based products for high volume, low manufacturing cost applications.

The big question, however, is the recyclability of traction batteries, the manufacture of which brings a significant environmental impact even before they are fitted to a vehicle. David Greenwood, Professor of Advanced Propulsion Systems at the University of Warwick, told the delegates that electric vehicle batteries typically cost between £5000 and £20,000 with a large proportion of that value embedded in the materials. He then showed a series of estimates that suggest that by 2040 there could be around £1 billion of battery materials to be recovered from end-of-life vehicles each year, if it is possible to develop designs and processes that make it possible.

Greenwood emphasised that with alternatives to lithium ion chemistry at least eight years away, the quest to achieve a closed supply chain is an urgent one and must begin now, with battery pack designers making recyclability a critical objective.

People are important too

Turning his lens onto the drivers of low emission vehicles, the University of Bath’s Dr. Robert Wragge-Morley suggested that consideration of how people accelerate and their choice of gears should be used to inform engine design decisions.

“Conventional teaching tells us to change up sooner and operate the engine in a high torque regime, where the thermal efficiency is best," he explained. "While this will reduce both fuel consumption and CO2 emissions, it raises cylinder temperatures and pressures which contribute to the production of NOx. Understanding this relationship, and the factors influencing driver satisfaction, could make a significant contribution to emissions reduction, especially in hybrid vehicles.”

“We must break down the silos,” he entreated. “We need greater integration, especially in energy infrastructure and in learning from related challenges.”

Meridian’s Al Clarke emphasised a similar theme when raising the topic of autonomous vehicles: “Cars will increasingly be integrated with other transport systems, with much higher utilisation rates as we move to full autonomy.”

The need to address these issues quickly was highlighted by James Beard of the World Wide Fund for Nature (WWF), who highlighted the latest figures for greenhouse gas emissions in the UK, published on the day of the seminar. Provisional UK government statistics show that while the decline in fossil fuel generation and increase in renewable energy has helped the energy generation sector reduce its emissions by 57% in the period 1990-2017, the overall reduction in vehicle tailpipe emissions was just 1% during that period with no improvement during 2017. Transport is now the largest contributor to UK CO2 emissions at 34%.

Three urgent EV environmental challenges

Summarising the key conclusions of the APC seminar, event chair, the Institution of Mechanical Engineers’ Head of Engineering Policy, Dr Jenifer Baxter, was clear that some serious questions need to be asked about the sustainability of electric vehicles.

“First, we must consider the whole-life emissions of electric vehicles and not just the tailpipe emissions," she said. "Second, it is essential that we accelerate the development of techniques for recycling batteries. Third, there are non-emissions environmental impacts that also deserve consideration, such as the impact of mining some of the materials that are essential to today’s EV technologies.”

The Advanced Propulsion Centre (APC) was established as a 10-year £1 billion joint investment between government and industry. The platform supports 36 major R&D projects worth £589 million, targeting a saving in excess of 34 million tonnes of carbon dioxide and creating or safeguarding 20,500 jobs.

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